• The Korean Journal of Mycology
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• v.50 no.4
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• pp.367-372
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• 2022

Leaf spot symptoms were observed in water spinach (Ipomoea aquatica) plants growing in fields in Ansan and Hongseong, Korea, during disease surveys in 2019 and 2020. The symptoms appeared as brown to dark brown circular or irregular spots on the leaves of the plants. The disease incidence on the plant leaves in the fields investigated at the two locations ranged from 1% to 20%. Five single-spore isolates of Phoma sp. Were obtained from lesions of the diseased leaves. All the isolates were identified as Ectophoma multirostrata based on their cultural and morphological characteristics, as well as molecular analysis. Two isolates of E. multirostrata were tested for pathogenicity on water spinach leaves using artificial inoculation. The tested isolates caused leaf spot symptoms in the inoculated plants. These symptoms were similar to those observed in plants from the investigated fields. To our knowledge, this is the first report of E. multirostrata causing leaf spot in water spinach.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2635-2639
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• 2013

The rapid and accurate identification of biological agents is a critical step in the case of bio-terror and biological warfare attacks. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry has been widely used for the identification of microorganisms. In this study, we describe a method for the rapid and accurate discrimination of Bacillus anthracis spores using MALDI-TOF MS. Our direct in-situ analysis of MALDI-TOF MS does not involve subsequent high-resolution mass analyses and sample preparation steps. This method allowed the detection of species-specific biomarkers from each Bacillus spores. Especially, B. anthracis spores had specific biomarker peaks at 2503, 3089, 3376, 6684, 6698, 6753, and 6840 m/z. Cluster and PCA analyses of the mass spectra of Bacillus spores revealed distinctively separated clusters and within-groups similarity. Therefore, we believe that this method is effective in the real-time identification of biological warfare agents such as B. anthracis as well as other microorganisms in the field.

• Journal of Fashion Business
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• v.8 no.3
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• pp.10-19
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• 2004

The purpose of this research is to reveal the antimicrobial activity of pet-dog clothes by investigating the bacteria resistance of 4 kinds of pet-dog clothes materials. 1. Investigation Results of Pet-Dog Clothes 64.7% of 150 survey participants, revealed they had pet-dog clothes. Hand laundering was 67.0%, while the laundering of both human and animal clothes was 9.2%. The greatest washing frequency was once every 2 weeks. So, the subjects didn't seem to think high of hygienic matters. Even though no if any relations were reported by 34.7% of the subjects, there were some experiences like sneezing or coughing (41.3%), slight itching (20.7%), and acute skin allergies. There were such hugging methods as heart to heart to the center (22.7%), face to face and around the mouth (16.7%), and below the heart with the dog's face outward (15.3%). Thus, hugging the dog near the pet-lover's face seems to be the cause of respiratory diseases including sneezes and coughs. 2. Results of the Anti-Bacteria Experiment of Pet-Dog Clothes Materials According to the analysis of the germs collected and cultured in this study to reveal the properness of pet-dog clothes materials, they were bacteria or bacilli in shapes. Spore growth was active in the order of such experimental materials as artificial leather > cotton > cotton/ nylon > polyester (finest thread). In terms of germ groups, the order was polyester(finest thread) > cotton > cotton/ nylon > artificial leather.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.49-54
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• 2012

In August 2010, a severe crown rot was observed on chrysanthemum ($Chrysanthemum$ $morifolium$ Ramat., variety Sinro) in several greenhouses located at Damyang and Muan, Jeonnam province, Korea. Three isolates (EML-CHS1, -CHS2, and -CHS3) of $Fusarium$ were isolated from the affected plants and identified based on morphological characteristics and rDNA internal transcribed spacer (ITS) sequence analysis. Sequence analysis by BLAST indicated that EMLCHS1, -CHS2 and CHS3 were closest to a $Fusarium$ species, $F.$ $solani$ with > 99% sequence similarity. Pathogenicity tests were performed on chrysanthemum with spore suspensions containing $3.4{\times}10^6$ spores/ml using the dipping method. Ten days after inoculation, similar symptoms to those observed in the greenhouses were seen on the inoculated plants. The causal fungus was reisolated from the artificially inoculated basal stems, fulfilling Koch's postulates. To our knowledge, this is the first report of crown rot by $Fusarium$ $solani$ on chrysanthemum ($Chrysanthemum$ $morifolium$) in Korea.

• Korean Journal of Organic Agriculture
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• v.23 no.1
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• pp.133-148
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• 2015

Although several adverse effects have been increased in recent years, synthetic agro-chemicals have been widely used to control diseases on paprika. This research was conducted to isolate and to characterize the antagonistic microorganism to control major paprika diseases, gray mold rot, fruit and stem rot, phytophthora blight, sclerotium rot, and wilt disease. Analysis of the fatty acid and analysis of the 16S rDNA gene sequence revealed that YKJ2 isolated in this research belongs to a group of Burkholderia cepacia. Specially, 16S rDNA gene sequence of YKJ2 showed 99% of sequence similarity with B. cepacia. Observation through the optical microscope revealed that YKJ2 was effective on suppression of the spore germination and the hyphal growth of pathogens. YKJ2 treatment on pathogens induced marked morphological changes like hyphal swelling and degradation of cell wall. In the case of phytophthora blight, the zoosporangium formation was restrained. On the basis of the results of this study, we propose that an antagonistic microorganism, B. cepacia, found in this study naming as "B. cepacia strain YKJ2" and has great potential as one of biological control agents against major diseases of paprika.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.306-311
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• 2014

In this study, arbuscular mycorrhizal fungi (AMF) were isolated and cultivated from rhizospheres of various plants in Korea. Five species belonging to four genus were identified based on spore morphology and 18S rDNA sequence analysis: Acaulospora cavernata Claroideoglomus luteum, Diversispora aurantium, D. trimurales, Rhizophagus irregularis. These fungal species have not been cultivated or reported to date in Korea, Morphological description and phylogenetic analysis for each species were presented. This result could be useful for research of AMF diversity in Korea.

• Journal of fish pathology
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• v.36 no.2
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• pp.303-310
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• 2023

Yellow goosefish (Lophius litulon) is one of the important commercial fisheries target species in Korea, and commonly consumed as braised or stew. The microsporidian Spraguea is known to infect the nervous system of lophiid fish, forming numerous visible whitish xenomas. This parasite is commonly found in lophiid fish worldwide, but there is no information on the infection status of this parasite in Korea. We obtained commercially available chopped packs of lophiid fish from several fish markets and investigated their prevalence of infection. The isolated xenomas were crushed and purified as mature spore suspension. Microscopic observation and PCR were conducted to visualize and identify them. The host fish was also identified by DNA bar cording analysis. All the specimens were heavily infected and microscopic observation with Giemsa or Chromotrope 2R stain revealed tiny oval shapes of typical microsporidian spores. PCR analysis targeting the partial SSU rDNA showed that our specimen belongs to the genus Spraguea clade. But clear identification at the species level was not possible, due to the insufficient information of gene sequences available in GenBank. In addition, all of our host fish specimen was identified as yellow goosefish. This is the first report of a microsporidian parasite Spraguea infection in yellow goosefish from Korea.

• Journal of Veterinary Clinics
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• v.27 no.2
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• pp.190-193
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• 2010

A 6-year-old, female, Siberian husky was referred with mucous diarrhea. On fecal examination, numerous clustered and individual large epithelial cells and rod-shaped, spore-forming bacteria were examined. By bacterial culture and molecular typing, the bacteria was identified as Clostridium perfringens (C. perfringens), and by toxin analysis of C. perfringens, production of $\alpha$-toxin was confirmed. Based on these results, the dog was diagnosed as enteritis caused by C. perfringens producing $\alpha$-toxin, and was treated with amoxicillin/clavulanate. After 1 week, the diarrhea was disappeared and no spore-forming bacteria were examined on fecal examination. This report shows that the rapid and exact diagnosis keeps a effective treatment for enteritis caused by C. perfringens producing $\alpha$-toxin in dogs.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.507-516
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• 2014

The present study was conducted to determine the effect of electron beam irradiation on control of Botrytis cinerea and postharvest quality of cut roses. Electron beam doses of 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 10, and 20 kGy were applied with a 10-MeV linear electron beam accelerator (EB Tech, Korea). Electron beams inhibited spore germination and mycelial growth of B. cinerea with increasing irradiation doses. Conidia of B. cinerea were more tolerant to irradiation than were mycelia: the effective irradiation doses for 50% inhibition ($ED_{50}$) of spore germination and mycelial growth were 2.02 kGy and 0.89 kGy, respectively. In addition, electron beam irradiation was more effective in reducing mycelial growth of B. cinerea at $10^{\circ}C$ than at $20^{\circ}C$. Analysis of in vivo antifungal activity revealed that elevated irradiation doses exhibited increased control efficacy for tomato gray mold. Flower longevity and fresh weight of cut roses decreased when the irradiation dose was increased. In addition, flower bud opening tended to be inhibited in a dose-dependent manner. Although 'Decoration', 'Il se Bronze', 'Queen Bee', and 'Revue' roses tolerated and maintained overall postharvest quality up to 0.4 kGy, 'Vivian' did not, demonstrating that the irradiation sensitivity of cut roses varies according to cultivar.

• Research in Plant Disease
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• v.15 no.3
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• pp.209-216
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• 2009

During the period of June, 2005 to May, 2008, 44 host plants infected with powdery mildew were collected in the Jeon-ju and Jang-su districts of Jeonbuk province and in the Jang-sung district of Jeonnam province. The hyperparasites, Ampelomyces were confirmed in 12 plant species. Most of the pycnidium shapes of Ampelomyces were circular or oval shaped, and the sizes were different even within the same host plant, and also the color of pycnidium was ranged from light brown to dark brown. Ampelomyces species were isolated from 4 hosts including Impatiens balsamina L., Cucurbita pepo, Rudbeckia laciniata var. elatier and Youngia sonchifolia, and thus the most appropriate 12 Ampelomyces strains for the current experiment were selected. When analyzing the selected 12 strains' incubational and nutritional characteristics, the malt extract agar was the most appropriate media. When investigating the effect of osmotic pressure on the spore germination, 0.15M NaCl concentration was the optimum germination concentration. When the isolated Ampelomyces sp. was tested in-vitro, it was found to be effective to control in other plant pathogens, isolated Ampelomyces showed no pathogenicity to the plant. strains isolated . studied on rDNA ITS sequence analysis. The rDNA ITS sequence data of Ampelomyces sp. isolate BSLAH16 from Impatiens balsamina L. were analyzed and identified.